Merge branch 'maint'

* maint:
  RelNotes 1.5.6.5 updates
  diff.renamelimit is a basic diff configuration
  git-cvsimport.perl: Print "UNKNOWN LINE..." on stderr, not stdout.
  Documentation: typos / spelling fixes in older RelNotes

diff --cc diff.c
Simple merge

diff --cc git-cvsimport.perl
Simple merge